Improvement in rock-drilling machines



AQJ. MERSHON. Rook-Drilling Machine.

No. 207,885. Patented se t. 10",- 187s.

WITNE$SES: 4 INVENTOR:

v a, mw/zw/ ATTORNEYS.

UNITED STATES PATENT OFFICE.

AARoN J. MERsHoN, or wARsAW, INDIANA.

IMPROVEMENT IN ROCK-DRILLING MACHINES.

Specification forming part of Letters Patent No. 207,885, datedSeptember 10, 1878; application filed July 22, 1878.

To all whom it may concern:

Be it known that I, AARON J. MERsHoN, of Warsaw, in the county ofKosciusko and State of Indiana, have invented a new and usefulImprovement in Bock-Drilling Machines, of

which the following is a specification:

This invention relates to certain improvements on the rock-drillingmachine for which Letters Patent No. 190,232 were granted to me underdate of May 1, 1877. In the machine described in said patent thedrill-shaft is operated by means of a revolving diskwheel provided witha curved slot, in which works one end of an arm, the other end of whichis provided with an eye, through which the drill-shaft works loosely. Asthe diskwheel revolves the arm binds on the drillshaft and raises it,and as the revolution of the shaft carries the arm beyond the centersaid arm drops and allows the drill-shaft to fall of its own weight.

The invention will first be described in connection with the drawing,and then pointed out in the claim.

In the accompanying drawing, Figure lis a side View of adrilling-machine embodying my improvements. Fig. 2 is an end view of thesame. Fig 3 is a transverse vertical section taken in the line was ofFig. 1.

Similar letters of reference indicate corresponding parts.

The drill-shaft A, lifting-arm B, disk-wheel O, and horizontal shaft (1are of the same general description as the corresponding parts shown inmy patent of May 1,1877, aforesaid, and arranged in a similar manner ina framework of the same general character.

To the sills of the frame which supports the working parts, at a pointbetween the diskwheel 0 and the drill-shaft A, is an upright plate, E,one edge of which is curved in the form of an arc of a circle verynearly corresponding with that described by the slot 0 in thedisk-wheel. This curved edge serves as a guide for the arm B, to preventit from being disengaged from the slot 0 when from any cause the arm maybe made so short as to render it liable to fly out of said slot.

G represents an arm similar to the arm B, being provided at one end withan eye, through which the drillshaft A works freely. About midway of itslength, on the upper side, rests the lower end of a spiral spring, H,the upper vided with a rod, h, for guiding it and preventing lateralvibration, which rod works in a socket in the abutment i when the springis compressed by the lifting of the drill-shaft, as hereinafterdescribed.

To the outer end of the arm G is attached one end of a spring, J, theother end of which is attached to the lower portion of the framework.This spring acts by compression, with a tendency to pull downward on thearm Gr and cooperate with the spring H to increase the descending forceof .the drill-shaft A.

To one of the upright end pieces ot'the frame work is attached a hook,L, arranged to hook under the arm Gr when desired and to swing out ofthe way when not in use.

The apparatus constructed as above described operates as follows: Whenthe diskwheel 0 revolves the lifting-arm B binds on the drill-shaft Aand lifts it, in the same manner as in the machine described in mypatent of May 1, 1877, aforesaid. In addition thereto the eye portion ofthe arm B bears under the eye portion of the arm Gr, causing it to risewith the drill-shaft A and to compress the spring H and expand thespring J. When the revolution of the disk-wheel brings the arm B to thehighest point and begins to carry it beyond the center, said arm Bleaves the arm G inclined sufficiently from a horizontal line, with itseye portion higher than its outer end, to cause it to bind on thedrill-shaft, with a tendency to pull it downward by the combined actionof the springs H and J. As soon as the arm B passes the center and dropsin the slot of the disk-wheel, the drill-shaft descends suddenly andwith great force, being aided therein by the combined action of thesprings H and J.

When it is desired to withdraw the drillingtool from the well or borethe arm G is raised to its highest position, and the hook L is hookedunder its outer end, so as to hold it slightly inclined, with its eyeportion lower than its outer end. In this position it is ready to bindon the drill shaft, with a tendency to pull upward on it. The disk-Wheelbeing now rotated the drill-shaft is lifted as before; but, instead ofdropping when the arm B passes beyond the center, the shaft A isarrested by the binding of the arm Gr upon it, and is held until againraised by the arm B on another revolution of the wheel 0. Thus at eachrevolution of said wheel the shaft A is raised a certain distance out ofthe well or bore.

If desired, the shaft d may be provided with gearing for transmittingmotion to it, instead of having the power applied directly to it.

In large machines for heavy drilling, instead of employing the arm G toarrest the descent of the drill-shaft when it is being withdrawn fromthe well or bore, as above described, another device may be employed,consisting of a frame provided with two steel plates hinged thereto, soas to swing toward and away from each other. The contiguous edges of theplates are provided with semicircular recesses, which, when broughttogether, form a circle slightly smaller than the diameter of thedrill-shaft A. When the machine is drilling the plates are swung outwardaway from each other, and the shaft A works in the frame to which theyare attached without touching them. When the shaft is to be withdrawnthe plates are swung toward each other, so as to bear against the shaftand bind on its surface with sufficient force to prevent it fromdescending, while at the same time it is free to ascend when raised bythe action of the disk-wheel C and lifting-arm B.

In cases where the shaft d receives its motion through gearing, insteadof directly, as above referred to, said gearing may also be arranged todrive an emery-wheel for the purpose of sharpening the drilling-tools.

I am aware that it is not new to use a spring that encircles the stemwhich carries one of the gripers for giving greater force to the drill;but 1 What I claim as my invention is The combination, with thedisk-wheel G and lifting-arm B, of the guide-plate E, substantially asshown and described, for the purpose specified.

AARON J. M ERSHON.

Witnesses:

MARsH H. PARKS, FRANK HUT'r.

